OPINION
¶1 Plaintiff Patricia Niemela appeals the trial court's grant of summary judgment in favor of Defendant Imperial Manufacturing, Inc., dba Imperial Mailbox Systems, (Imperial) in her products liability action. We affirm.
BACKGROUND
¶2 Niemela delivered mail for the United States Postal Service (USPS). Starting in 2001, her route included approximately 600 homes within the Overlake Homeowners' Association (the HOA) in Tooele, Utah. Nearly every home in this neighborhood had the same type of mailbox, manufactured by Imperial; in fact, the HOA fined homeownеrs who did not use the Imperial mailbox. Imperial designed and manufactured the mailboxes in 1995 and sold them to the Overlake developer sometime between 1995 and 2001. However, the mailboxes were not installed until 2001. 1 The mailboxes were designed with a three-quarter-inch circular knob on the door and holes in the top to affix an address plate. Allegedly due to the material with which the door hinges were made, over time the door would not align perfectly with the mailbox, allowing water to enter and freeze the door shut in cold weather. When a mailbox was frozen shut, Niemela would frequently use a hammer and serewdriver to pry it open; she also stated that the doors would catch when opened even when there was no ice.
¶3 After two or three years of delivering mail in the Overlake neighborhood, Niemela began to notice cramping and mild pain in her right hand when she had to force open a mailbox. She alleges that on December 5, 2005, she suffered a serious and permanent injury to her hand whilе struggling to open a mailbox. Her right hand was already inflamed and sore early into her route that day when, struggling to open another mailbox, she felt a shot of pain go up her arm. After resting at her nearby home, she finished her route using a hammer and screwdriver to open other frozen mailboxes. Niemela sought medical attention for her hand and was unable to return to full-time employment delivering mail with USPS.
¶4 Niemela brought a products liability action against Imperial, alleging strict liability, negligence, and breach of implied warranty for design and manufacturing defects. Af ter discovery concluded, Imperial moved for summary judgment, which the trial court granted. Niemela appeals.
ISSUES AND STANDARD OF REVIEW
¶5 Niemela challenges the entry of summary judgment in favor of Imperial, both as to her products liability claim and her negligence claim.
2
In determining whether summary judgment was appropriate, we view "the facts and all reasonable inferences ... in the light most favorable to the nonmoving party." Jensen ex rel. Jensen v. Cunningham,
ANALYSIS
I. Products Liability
¶6 In her products liability claim, Niemela alleges that the Imperial mailboxes contained design and manufacturing defects rendering them unreasonably dangerous. She seeks to *1195 demonstrate these defects by showing that the mailboxes did not conform to the 2001 USPS regulations, notwithstanding the fact that the mailboxes were designed and manufactured in 1995. Imperial responds that (1) the mailboxes must be presumed nondefec-tive because they complied with federal regulations in effect when they were designed and manufactured, and (2) Niemela has not presented sufficient evidence to overcome this presumption.
¶7 Summary judgment "shall be rendered if ... there is no genuine issue as to any material fact and ... the moving party is entitled to a judgment as a matter of law." Utah R. Civ. P. 56(c). "A plaintiffs failure to present evidence that, if believed by the trier of fact, would establish any one of the [elements] of the prima facie case justifies a grant of summary judgment to the defendant." Stevens-Henager College v. Eagle Gate College,
¶8 "Products liability claims require proof of a defective product, which can include manufacturing flaws, design defects, and inadequate warnings regarding use." Dimick v. OHC Liquidation Trust,
¶9 Although the tort of strict products liability is a creature of common law, see Brown v. Sears, Roebuck & Co.,
In any action for damages for personal injury, death, or property damage allegedly caused by a defect in a product, a product may not be considered to have a defect or to be in a defective condition, unless at the time the product was sold by the manufacturer or other initial seller, there was a defect or defective condition in the produсt which made the product unreasonably dangerous to the user or consumer.
Utah Code Ann. § 78B-6-703(1) (2008). As defined by the Act, the standard for "unreasonably dangerous" focuses on consumer expectations:
As used in this part, "unreasonably dangerous" means that the product was dangerous to an extent beyond which would be contemplated by the ordinary and prudent buyer, consumer, or user of that product in that community considering the product's characteristics, propensities, risks, dangers, and uses together with any actual knowledge, training, or experience possessed by that particular buyer, user, or consumer. -
Id. § 78B-6-1702, The United States Court of Appeals for the Tenth Cireuit has read this statute to encompass both an objective and a subjective consumer expectations test. See Brown,
¶10 The statute also creates a rebuttable presumption of nondefectiveness applicable to a product compliant with government standards:
There is a rebuttable presumption that a product is free from any defect or defective condition where the alleged defect in the plans or designs for the product or the methods and techniques of manufacturing, inspecting and testing the product were in conformity with government standards established for that industry which were in existence at the time the plans оr designs for the product or the methods and techniques of manufacturing, inspecting and testing the product were adopted.
Utah Code Ann. § 78B-6-703(2). To overcome the presumption, the plaintiff must prove by a preponderance of the evidence that the product is unreasonably dangerous. Egbert v. Nissan North Am., Inc.,
¶11 The mailboxes at issue here were designed and manufactured in 1995. As Niemela has acknowledged, in 1995 the USPS found them to conform to its then-current 1992 regulations. The mailboxes thus enjoy a presumptiоn of nondefectiveness based on the 1992 regulations. See Utah Code Ann. § 78B-6-708(2). However, the USPS regulations were revised in 2001. Niemela seeks to rebut the presumption of nondefectiveness by showing that the mailboxes were not in compliance with the 2001 regulations.
¶12 The Act itself forecloses Niemela's argument. Section 78B-6-703(2) specifies that the relevant government standards are those "in existence at the time the plans or designs for the product ... were adopted." Id. Niemela advocates an аpproach that would permit a presumption based on government standards in existence at the time the product was designed to be rebutted by reference to later government standards, even if the later standards were not in existence at the time the product was designed. This approach would, contrary to the statute's clear requirement, make the touchstone of the presumption compliance with government standards not yet "in existence at the time the plans or designs for the product ... were adopted." See id.
¶13 Niemela also argues that, even without resorting to the 2001 governmental standards, "[t]he litany of problems posed by the small knob Imperial mailbox is sufficient to create an issue of fact as to defective design." She devotes only a single paragraph to this argument, citing the following characteristics as evidence that the mailbox *1197 was unreasonably dangerous: (1) the handle diameter was too small; (2) the handle depth was too shallow; (8) holes in the top of the mailbox allowed water to enter and ice to form at the hinge; and (4) the door hinges were exposed, further allowing water to enter and freeze. In arguing that these characteristics made the mailbox more dangerous than would be contemplated by the ordinary and prudent user, she refers to "the stark difference between the Imperial mailbox in question and the Imperial mailbox with the larger, deeper knob." She also refers to "the difference between the Imperiаl mailbox in question and the ordinary aluminum mailboxes." This is the sum and substance of her argument.
¶14 In our judgment, the mailbox flaws Niemela cites are insufficient evidence for a jury to conclude that the mailbox was "dangerous to an extent beyond which would be contemplated by the ordinary and prudent . user of that product ... considering the product's characteristics, propensities, risks, dangers, and uses together with any actual knowledge, training, or experience possessed by" Niemela. See Utah Code Ann. § 78B-6-702 (2008). Proof that the plaintiff was injured by a product, without more, is insufficient to establish that a product is unreasonably dangerous. See Kleinert v. Kimball Elevator Co.,
¶15 This would be quite a different case if Niemela could show that the mailbox violated applicable safety standards designed to protect against the injury she experienced. See Gudmundson v. Del Ozone,
II. Negligence
¶16 Niemela also contends that Imperial was negligent in designing and manu
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facturing a defectivе mailbox. The trial court rejected this claim on several grounds, including that she had failed to establish both duty and proximate cause. See Stevens-Henager College v. Eagle Gate College,
¶17 A plaintiff claiming negligence in this context must prove the ordinary elements of negligence, including duty and causation. See, eg., Slisze,
¶18 The trial court ruled that Niemela failed to prove duty; in particular, she "failed to show that [Imperial] had prior knowledge or any knowledge that the manufactured handles/knobs caused injuries or were in any way defective." In addition, the court ruled, she failed "to provide expert or other testimony regarding the design of the handles/knobs of the mailboxes at issue."
¶19 When ascertaining whether a duty of reasonable care exists, a court should consider the following factors: "(1) the extent that the manufacturer could foresee that its actions would cause harm; (2) the likelihood of injury; (8) the magnitude of the burden of guarding against it; and (4) the consequences of placing the burden on the defendant." Slisze v. Stanley-Bostitch,
¶20 Niemela's brief does not discuss these factors. It cites one case for the unobjectionable proposition that "failure to manufacture a product according to a safe design plan can result in liability" (citing Jacobsen Const. Co. v. Structo Lite Eng'g, Inc.,
¶21 This level of briefing is not adequate; accordingly, we decline to reach the merits of this argument. See Utah R.App. P. 24(a)(9); State v. Thomas,
¶22 We see the issue of causation in much the same light. The trial court ruled that Niemela "failed in her burden to present evidence that her injuries were the proximate and actual result of {Imperial's] mailboxes." "[The causal connection between the alleged negligent act and the injury is never presumed{[,] and ... this is a matter the plaintiff is always required to prove affirmatively." Fox v. Brigham Young Univ.,
¶23 Again, Niemela's briefing on this point is inadequate. She devotes only three sentences to challenging the trial court's ruling on causation. She distinguishes Fox v. Brigham Young University,
¶24 We recognize that lawyers operate within practical constraints. These might include the lawyer's workload, the client's resources, and the estimated value of the particular case. We also recognize that these constraints may be especially limiting for lawyers representing private individuals rather than institutional clients for whom litigation may represent a cost of doing business. Nevertheless, our system is designed so that the "аppellant must do the heavy lifting," State v. Robison,
CONCLUSION
¶25 With respect to Niemela's products liability claim based on strict liability, we agree with the trial court that Imperial is entitled to the presumption of nondefectiveness based on the uncontested fact that the mailboxes at issue conformed to government standards in effect at the time of their design and manufаcture. The fact that these mailboxes were arguably inferior to later Imperial designs or to a more traditional design, *1200 and that Niemela was allegedly injured by opening and closing the mailboxes over a million times, fails to demonstrate that they were unreasonably dangerous. In addition, Niemela's products liability claim based on negligence is inadequately briefed.
¶26 Accordingly, we affirm summary judgment for Imperial.
¶27 WE CONCUR: WILLIAM A. THORNE JR. and STEPHEN L. ROTH, Judges.
Notes
. While there is some discrepancy as to when the mailboxes were sold and installed, this issue is not material to the resolution of this case.
. Niemela does not address the trial court's dismissal of her breach of implied warranty claim. We therefore deem this claim waived.
. For twenty-three years, even the ostensibly statutory standard was effectively based in common law. The statute was declared void in 1985 and not re-enacted until 2008. See Egbert v. Nissan Motor Co.,
. The proof required to rebut the presumption appears to be identical to the proof required to establish the first element of a prima facie case. See Dimick v. OHC Liquidation Trust,
This fact has prompted some to suggest that "'the statute is of no benefit to the manufacturer." Egbert v. Nissan North Am., Inc.,
In addition, the Legislature may have envisioned a case where the plaintiff attempts to rebut the presumption by showing that a product, though compliant with government standards, is unreasonably dangerous in a way those standards do nоt contemplate.
. Niemela alleges that she "opened and closed nearly 600 Imperial mailboxes every day, five days a week, fifty-two weeks a year for seven years."
. It is far from clear that even the inapplicable 2001 regulations upon which Niemela relies are aimed at carrier safety rather than convenience, efficiency, or protection of the mail from the weather. For example, those regulations require that "[the handle or knob shall have adequate accessibility to permit quickly grasping and pulling it with one hand," 66 Fed.Reg. 9512, § 3.4.1 (Feb. 8, 2001) (emphasis added), not safely grasping and pulling it with one hand. In contrast, Niemela does not rely on those portions of the regulations explicitly aimed at safety, such as the section stating that "[the unit must not have sharp edges, sharp corners, burrs or other features (on any surfaces) that may be hazardous to carriers/customers." Id. § 3.14. In any event, because we have already decided that the 2001 USPS regulations do not control here, and because the parties did not brief the distinction between regulations aimed at carrier safety and regulations aimed at other concerns, we need not examine the distinction.
. Even on the merits, however, we regard Niemela's claim as doubtful. Niemela compares herself to "the plaintiff who trips and falls, breaking a wrist"; in both cases, she asserts, causation "is apparent even to a lay person." However, unlike an injury resulting from a fall, the mechanism of causation alleged here involves no moment of impact. Rather, the injury allegedly occurred gradually over a seven-year period as Niemela "opened and closed nearly 600 Imperial mailboxes every day, five days a week, fifty-two weeks a year for seven years." We do not agree that this is among the most obvious cases where "the causal connection between the breach of the standard of care and the harm suffered is apparent using common knowledge." Bowman v. Kalm,
